Explanation

Before & Within

Before = point of time

Within = period of time

Please go there before Friday.

Finish it within two days means اس کو دو دنوں میں مکمل کرو

Explanation

Generally familiar is followed by with.

With is a preposition here.

He is familiar with me وہ مجھ سے واقف ہے

Explanation

Find is a verb.

Find means پانا

Found is the third form of find.

Have you found your dog?

Explanation

We generally use preposition By before transports like by bus, by car, by air etc. 

Explanation

"Can" is one of the most commonly used modal verbs in English. It can be used to express ability or opportunity, to request or offer permission, and to show possibility or impossibility

Explanation

He is speaking at the back of his best friend.

At the back of means کے پچھلے حصے میں

Explanation

By the stroke of luck, the troops prevailed, avoiding a crushing defeat.

Explanation

"Room" refers to available space within an enclosed area.

Room means کمرہ

There is no room in this compartment.

اس ٹوکری میں کوئی گنجائش نہیں ہے۔

Explanation

This sentence belongs to Future Perfect Tense.

Formula: Subject + will + have + 3rd form of a verb + object.

Explanation

The word "unless" is an adverb which means جب تک